Improvement in compositions for pavements



To all whom it may concern preparations. 1

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[ OHIARLESVBQHARRIS, OF New YORK, N. Y.

Letters Patent No. 112,339, dated March 7, 1871 antedeted February 25, 1871.

IMPRO VEMENT IN QOMPOSlTIQNS FOll PAVEMENTS.

Be itlinowu that LOIIARLES B.,HA1mIs, of the a [city and county of New York and State of NewYork',

have-inventeda new'and useful Composition for Paving,,Flooring, Roofing, and other similar purposes; andI ,do hereby declare that thefollowingisa full,

clear, and exact description thereof. V

This invention relates to an improvement in compositions. for paving, flooring, and similar purposes,

which are composed in part of natural or artificial asphaltuin or bitumen.

My iventiop consists in altering or subduing the excessive plasticitygwhich the asphaltic materials have atjthe increased temperatures of the climate by the addition of steatite and clay eitherl or both; the latter named substances having of themselves an unctuous or non-gritty nature, they add none of that brittle or granular character to the asphaltic compound, in

this respect diii'ering from all silioious and granular The inveutioirfm'ther consistsin the addition to the above-named materials of mica 01' micaceous rocks.

The mica has the property of binding the whole mass, when laid, 'in such a way that it is better enabled to resistrupture by sudden changes of temperatureor by shock; and it has also an elastic nature,

which is imparted to the compound. V horouglily mixed, cemented, and compressed with asphalt, have sucll Themica, steatite, anl clay, when t properties that thewear and tear of attrition is reduced to a minimum.

The miraceo'us rock, the steatite,'.jandthc clay are subjectedto the-following mechanical treatment: i i 'lhe rfiieaceousrock is brought to a state of fine dijvision b Q gneans of machinery that is ordinarily used for simiiaaypurposes, audthe mica is as thoroughly separated'from other-materials as possible by means i of the'm'dinary methods of screening, or preferably by ytheforee of winddriven through the powdered rock.

" l .l'ha Bchellul referred to in these Letters Patent and part of the same.

The steatite and clay are. powdered by grinding or by crushing, and then screened from the coarser powder.-

' fter these materials have been mechanically treated substantially as above described they are mixed in proportions best suited to the case, and then heated to about 300 Fahrenheit, and stirred vith the melted aspbaltfto a coherent waxy mass, when it is ready for application. In some instances it may be applied to well-prepared ground, but generally it must be preceded by an asphaltic or a hydraulic concrete or base.

In all cases it is necessary to compress the freshlyprepared material (after it has been spread) while yet hot, by means of tampers or rollers.

When used for roofing or tiling it may be either laid in one continuous sheet, or in tiles or bricks, cemented with asphalt. it

The proportions of clay, steatite, and mica depend upon the character of the wear and tear the material will be subjected to. I

For streets and roads there should be about onethird 1;) of an equal mixture of clay and steatite, and two-thirds (3) of mica.

Forsidewalks or paths :1. larger proportion of steatite than clay should be used.

For floors and cellars clay (without steatite) mixed with about fifty (50) per cent. of mica may be used to the best advantage.

What I claim as new, and desire to Letters Patent, is-

A composition for paving, flooring, and roofing, composed of steatite and clay, together with mica or secure by 'micaceous rocks, crushed or pulverized, and mixed with asphalt, as herein described and set forth.

CHARLES B. HARRIS.

Witnesses:

JOHN C. ADAMS,

HIRAM P. Onorrurr. 

